Table 1.

A risk stratified approach to decision making in probable or proven papillary microcarcinoma

Candidates for observation	Tumor/neck US characteristics	Patient characteristics	Medical team characteristics
Ideal	Solitary thyroid nodule Well-defined margins Surrounded by ≥2 mm normal thyroid parenchyma Absence of extrathyroidal extension Previous US documenting stability Absence of lymph node metastasis Absence of distant metastasis	Older patients (>60 years) Willing to accept an active surveillance approach Aware of that a surgical intervention may be necessary in the future Willing to participate in follow-up plans Supportive significant others (including other members of their health care team) Life -threatening comorbidities	Experienced multidisciplinary management team High-quality neck ultrasonography Prospective data collection Tracking/reminder program to ensure proper follow-up
Appropriate	Multifocal papillary microcarcinomas Subcapsular locations not adjacent to the RLN without evidence of extrathyroidal extension Ill-defined margins Background ultrasonographic findings that will make follow-up difficult (thyroiditis, non-specific lymphadenopathy, and multiple other benign-appearing thyroid nodules) FDG avid PTMC	Middle-aged patients (18–59 years) Strong family history of papillary thyroid cancer Child-bearing potential	Experienced endocrinologist or thyroid surgeon Neck ultrasonography routinely available
Inappropriate	Evidence of aggressive cytology on FNAB (rare) Subcapsular locations adjacent to the RLN Evidence of extrathyroidal extension Clinical evidence of invasion of the RLN or trachea (rare) N1 disease at the initial evaluation or identified during follow-up M1 disease (rare) Documented increase in size of ≥3 mm in a confirmed papillary thyroid cancer tumor	Young patients (<18 years) Unlikely to be compliant with follow-up plans Not willing to accept an observation approach	Reliable neck ultrasonography not available Little experience with thyroid cancer management

US: ultrasound; RLN: recurrent laryngeal nerve; FDG: fluorodeoxyglucose; PTMC: papillary thyroid microcancer; FNAB: fine needle aspiration biopsy.